The microwave oven has become so popular that it's rare to find a home without one. They make cooking quick and easy and have spurred the creation of many microwave-ready foods. But there are two types of microwave ovens--the conventional microwave and the convection microwave. They are similar in many basic ways, but have different capabilities. Knowing the difference may help you decide which one to buy.
Microwave technology is basically the same in both the conventional and the convection microwave. Both devices emit microwaves that pass through the glass or plastic cooking containers and penetrate the food. All food has some amount of water inside it. The electromagnetic energy of the microwave causes the water molecules to move quickly, which creates friction that in turn creates heat. This heat cooks the food. Neither the conventional or convection microwave has an advantage when it comes to standard microwave technology.
The main difference in the conventional and convection microwave is akin to the difference in the standard oven and the convection oven. The standard oven, like the conventional microwave, uses a single source of heat to cook the food. Although they are different, they are similar in that there is no moving air inside the cooking chamber. Both convection ovens and convection microwaves use a fan to circulate air inside them to evenly distribute the heat. This makes for quicker cooking in the convection microwave.
The way a convection microwave cooks is not only advantageous because it is faster, but it also cooks in two ways instead of just one. In addition to quickly cooking the item using microwave technology, the circulating heat, and sometimes a radiant heat source inside, actually browns meats or crisps breads. Conventional microwaves cannot brown the skin on a chicken or make a pizza crust crunchy, for example, but a convection microwave can do it and do it fast.
A common complaint about microwave-prepared foods is that the food, no matter how delicious its potential, often comes out bland or otherwise lacking the expected flavor. This is because a conventional microwave's technology produces a type of cooking similar to steaming. This can sometimes neglect the flavor potential, appearance and texture of some foods. A convection microwave can have these same results if desired, but it can also mimic roasting or baking. You'd never be able to bake a pie in a conventional microwave, but in a convection microwave it's a snap.